Electric-lighting system



May 27, 1924.

. E. FUCHS ELECTRIC LIGHTING SYSTEM Filed DeoJl v4 Hg. i

Inventor.

Patented May 27', 1924.

UNITED STATES PATENT OFFICE.

ERNEST FUCHS, OF PARIS, FRANCE, ASSIGNOR TO LOUIS RENAULT, 0F BELLANCOURT,

' FRANCE.

ELECTRIC-LIGHTING sYs'rEnE.

Application filed December 81, 1919. Serial $48,708.

To all whom it may concern Be it known that I, ERNEST FUCHS, citizen of the French Republic, residing at Paris, Department of the Seine, in France, having P. 0. address 111 Boulevard Lxelmans, in the said city, have invented certain new and useful Improvements in Electric- Lighting Systems, of which thefollowing is a specification.

The present invention relates to safety devices for electric lighting circuits, more particularly to electric lighting circuits as used in automobiles and other vehicles, where the lamps are fed .by a dynamo and a battery of accumulators included in the circuit.

In existing electric lighting systems if from any cause whatsoever the accumulators fail, or if a connection becomes broken, the voltage instantaneously rises in the circuit, and if the speed of the vehicle is sufficient, the lamps are immediately burnt out.

These inconveniences may have very'serious effects, at night, for example, when a vehicle is running at full speed.

In order to avoid this danger a great number of systems have been proposed having for their object to maintain a constant voltage, or at leasta voltage between given limits in the circuits under consideration. These regulating or controlling systems are. generally very complicated and hence the reason for the frequent use of a simple in stallation, without a regulator or controller, in spite of the inconveniences enumerated above.

The devices forming the subject of the 1 present invention have been designed with the view of efiicaciously protecting the lamps without the use of a controller or regulator and without unnecessarily complicating the installation.

In order that the invention may be clearly understood reference is made to the accompanying drawing which shows diagrammatically in Figures 1 to ivarious arrangements in accordance with the present 1nvention. Although the arrangements shown differ slightly from each other, they all embody the same very simple principle which consists in inserting automatically in parallel an auxiliary resistance such that f the voltage cannot appreciably increase at the maximum. speed of the motor and there by burn out th'elamps when the accumulators are ino erative or when a connection becomes brolgen as hereinbefore indicated.

In all the figures the same reference letters indicate the sameparts.

The generatorlis-indicated at a, the battery of accumulators at b, and the lamps placed in parallel at 3,0 0-,. v

The resistancelinserted in parallel in the circuit is shew" :at Z. The safety device which is therep'laqed in circuit comprises the followingu'inembers, a solenoid having a soft iron core (1', afrockable lever 2' having a piece of soft irony e at one of its ends, the other end hiring a catch which in normal running preventsithe displacement of a rockable lever gwhich lever is provided with a contact piece} ar na end, the other end being constantly u der the action of a spring 72, which contact. piece makes contact with the terminahkloonnected in the circuit when the lever z' swings-on its pivot under the attraction of the solenoid core 01. I

The value of the resistance Z is such at the greatest speed of the dynamo, the battery b being cut out of the circuit, that the voltage cannot rise sufiiciently to cause burning out of the lamps.

The action is quite simple. When the tension attains a. given value (corresponding to an excess voltage of 15 to 20% for example) the lever 71 is attracted and the contacts 7' and k are closed and the resistance l is thus inserted inthe circuit; at this instant there is a decrease in voltage, unless the dynamo rotates at its maximum speed; this decrease in voltage will generally diminish the intensity of the lighting, but the lamps will not be burned out. Besides the attention of the driver will be directed to the condition of the installation, the decreased lighting efiect indicating to him that there is some defect which ought to be remedied when convenient. In any case there will be no necessity to, stop the vehicle.

Figure 2 shows a modified arrangement of that hereinbe fore described, which consists in substituting for the resistance 1 of Fi ure 1, a small accumulator of the alkali type. Alkaline accumulators can absorb without the danger of heating, a large number of amperes in a small mass; further, they are not subject to sulphating action. They can therefore ensure the lighting of the vehicle, but by reason of their low output they cannot be employed for starting.

In the two arrangements hereinbefore described, the insertion in the circuit either of the resistance or of the auxiliary accumulator-is effected by the action of the lever i and the co-acting detent on the lever g.- Therefore as soon as the lever i has been operated to release the lever 9, it remains in the altered position. It is obvious that the form thereof can be varied without departing from the nature of the invention.

In the arrangement shown in Figure 3, the pawl of the lever i is replaced by a trembler switch. In this arrangement the core cl of the solenoid attracts the lever Z at the proper time, which lever is maintained clearof the core by the spring 12-; the insertion in the circuit of the resistance Z is made when the contacts 9' and k are closed. Since there is an abnormal rise in volt-age on the line, the core d attracts the mass 0-; the contacts 7,70 close and the current flows through the: resistance Z and the voltage is lowered immediately; the spring h then restores the lever Z to its original position and so on.

The oscillation of the lever Z' thus ensures a practically constant voltage in the line, in spite of. deterioration in the condition of the battery 6.

In order that the driver may be warned that there is something wrong with the installation, a lamp a may if desired be placed within range of his vision, the said lamp being connectedin parallel with the resistance Z when the lamp lights up, it indicates that the safety device is in use, and that there is something wrong wit-h the installation. 1 i

In the arrangement shown in Figure 4, the resistance to be inserted in the circuit instead of being separated from the solenoid, is superposed on the winding of the latter-in such manner that its action is add ed to that ofthe solenoid in order to maintain the mass e attracted by the core of the solenoid.

In this arrangement, the action is not that of the trembler of Figure 3. As soon as the voltage in the circuit rises above a certain percentage, the core d attracts the mass 0; the circuit is closed through the resistance Z, the voltage is lowered, and the electromagnetic force of the solenoid decreases: but, the circuit through the resistance Z being closed, a new electromagnetic force is added to the former on the core of the solenoid and the mass 6 is maintained against the core as long as the voltage is not reduced below a certain percentage of its normal value When this decrease in voltage takes place the spring h comes into action and the resistance is cut out of the circuit and the voltage rises and the arrangement operates anew only when the predetermined perignition at the sparking plugs and consequcnt stoppage of the motor.

lVith the arrangements hcreinbefore described this danger is practically avoided, because there are two batteries of accumulators, either of which can be used if the other be damaged. There is therefore no fear of lack of current for ignition purposes, especially if a battery of the alkaline type be employed, which is not liable to any sulphating action. Under these circumstances, suppression of the magneto becomes possible without fear of being held up or stopped. Various inventors have proposed as auxiliary aids the use of electric cells but these present the inconvenience of deteriorating on open circuit and consequently fail to give sufiicient security.

1n the arrangement where use is made of an alkaline battery such as m for ignition purposes, the ignition circuit is naturally branched to the two terminals of this battery. Besides it is necessary in this arrangement to connect the terminal r'of the battery corresponding to the contacts 7', k, in Figure 2, with the main circuit through a make and break switch .9, shown in'dotted lines in Figure 2.

In all the arrangements hereinbet'ore described, the value of the solenoid and resistance are chosen so as to maintain the variations in voltage within normal limits, thereby ensuring safety without the variation becoming too low or rising too high.

Claim:

In an electric lighting system, thecombination witlra storage battery and a charging dynamo in a common circuit with lamps in parallel connection therewith, a resistance clement interposed in said circuit in parallel arrangement with the lamps, a pivoted switch controlling the resistance circuit, means normally tending to move the switch to close theresistance circuit, a' detent normally engaging said switch to hold the same open. and a solenoid in the circuit in parallel arrangement with the lamps to be energized by excessive voltage to actuate the detent to release the switch to ,close the resistance circuit, the values of the resistances In testi nony whereof I hai'e hereunto set ofthe rheostat and of the resistance element. my hand 1n presenceof two subscribing witbQlIlgSllCh that the voltage a'cross the lamp nesses.

circuit cannot exceed the capacityef the I ERNEST FUCHS. 5 lamps with the storage battery cut out pf Witnesses:

the circuit and the dynamo driven at Rs LOUIs Jesse,

maximum speed.

Emu: Kwrz. 

